| Popis: |
Autonomous driving is an important research field and presents several problems with different nature and complexity. The goal of this work is describing such problems and the concerning solutions adopted while developing an experimental vehicle designed to autonomously perform some manoeuvres and/or to be remotely driven: the vehicle RUMBy. The problem has been faced from its beginning, i.e. from the hardware and software design: the requisites the system should satisfy are discussed, such as the vehicle and the sensors chosen, and the adopted hardware and software architectures are then described. Some mathematical models representing the vehicle dynamics are also presented, that have been employed in several applications, from the dynamic behaviour simulation up to the control system synthesis. Each model besides presents characteristic parameters that should be evaluated: therefore the problem of identification is discussed in detail, accompanied by the results obtained during an experimental activity carried out in collaboration with a Japanese research institute. Also the vehicle state estimation constitutes a key point in autonomous driving field: about this, the experimental results yielded by an estimation algorithm, based on a Kalman filter, are presented and discussed. Finally, the yaw rate control problem is examined, which is fundamental for both the motion stabilization (during remote driving) and for the following of yaw rate reference profiles (while performing autonomous manoeuvres). Two control architectures, based on a disturbance observer, have been developed and compared in a simulation campaign, that has been carried out by means of a static simulator which reproduces the driving of RUMBy in a virtual environment. This work aims then at marking a milestone within a work in progress, as well as at representing a potential guideline for researchers that would coping with projects concerning autonomous driving. |
